Most people who have tried dieting for weight loss, know those days or weeks when you eat less are always, annoyingly rough.

As it turns out, one specific group of brain neurons may be to blame for those unpleasant, hangry feelings that make it super difficult to stick with it, says a new study.

"If hunger and thirst didn't feel bad, you might be less inclined to take the risks necessary to acquire food and water," says Scott Sternson, Ph.D., a researcher at the Howard Hughes Medical Institute and co-author of the study.

Sternson and his colleagues found that, when mice lost weight, a group of neurons called "AGRP neurons, switched on and seemed to foster "unpleasant or negative emotions" in their little rodent brains.

Sternson also says it's already been shown that these hangry neurons exist in people's brains too.

It may seem obvious that going hungry would lead to "bad" feelings, but Sternson's study is one of the first to explain where these bad feelings come from.

He says AGRP neurons live in the part of your brain that helps regulate everything from hunger and sleep to your emotions.

Sternson and his team also showed that, by switching off these AGRP neurons in mice, they were able to influence the types of foods the mice preferred and even the places they liked to hang out.

Creating a drug that silences these hangry neurons could be a great weight-loss aid, he says.

Taking the research to another hypothetical level, if you tend to snack a lot on your couch at home, these neurons could play a role in strengthening your desire to stick with that unhealthy habit.

But all that's for the future, Sternson explains. "At this point, our study just provides a bit more awareness of what people are up again when they try to lose weight," he says. "People need a plan and they need social encouragement to overcome these negative emotions."